Computer viruses are programs that are written by hackers or crackers for weakening the protection of the computer and making it infected. They usually occupy huge disk space and thus there might occur system crashes more often. Viruses will be doing things without even making the user aware about them. The user won’t be even knowing that the virus have already started its works. People usually become aware about it only when the virus closes all the doors for removing it from the system. There are different types of computer viruses and they are employed to do different tasks. Here we’ll be going through the different types of computer viruses that are mostly seen in our computers. After you learn about the different types of computer viruses, you will be getting an idea regarding how to spot viruses and remove them from your system the easy way without seeking anyone’s help.

Macro Viruses

Macro Viruses are one of the most commonly seen computer viruses. These are platform independent viruses and hence they are seen in applications. They will be making the application malfunctioning and thus we won’t be getting the desired results out of it. These viruses are ported directly into the desired applications for which it has been written. But don’t think that they won’t be doing any harm to other parts of your system. They will surely be harming the whole performance of your computer. These viruses, just want a host to do its job and in this case, the applications are its host and they perform their job from there. After they reside in a particular application, they will be starting their work and will be infecting the system in no time.

And since, they are not staying in the hard disk of the computer; they won’t get deleted just by deleting the infected files. And if you don’t have any idea about macro viruses, you will simply be deleting the infected files thinking that those are computer viruses. Macro viruses can’t be deleted that easily. First of all you should be finding out, which is the application that has got infected with the virus. For that you should be opening each of the application programs that have already been installed in your computer and should be noting down differences in their performances. If you find something unfamiliar, you can almost make sure that the application has got infected, and then re-install it.

Network Virus

One of the other types of computer virus is a network virus, and they are spread through local area networks and internet. Once spread they will find out other computers in the network which are not infected. The virus will get copied to other computers this way. And from those computers, it will again get copied to other computers. The process will go on as a cycle and will finally affect all the computers in a network. Nimda is one of the most dangerous network virus at the moment. If you are thinking of protecting your system from viruses of this kind, then you should be installing a good anti-virus program that is with the capability to find and destroy anti-viruses of all kinds.

But for that, you should be updating the program every now and then through the internet. If you are ready to go with things this way, then there won’t be problems for you from viruses of any types.

Logic Bomb

The next type of computer virus that we are going to study is Logic Bomb. Actually these are lines of code that are embedded into software systems in our computer. These won’t be functioning until a specific condition is met. Until that point, it will be simply residing in the software system without doing any harm to the computer or the computer user. That’s the reason why the virus has got the name Logic Bomb. It will start functioning only when a specific condition becomes true. That time, the script will get activated and the outcome might be seen the same instant. People usually activate such viruses on special days like April fool day and such.

Companion Viruses

One of the rarest computer viruses is companion viruses. These viruses cannot do much harm to today’s systems since they are all installed with Windows XP. Companion viruses works only in the MS-DOS environment. We usually do not enter the extension, if the file that we want to open is an executable file. At such a situation, the companion virus will get opened and it will start functioning. That’s because, when we don’t enter the .exe extension, the system will look for the lowest alphabet and it will find .com extension files which would be companion viruses.

Companion viruses can be seen in .com extensions as well as .exd extension. The companion virus will be having the same filename as that of the executable file. Only the extension of the companion virus will be different from the executable file. This is the reason why a companion virus gets opened when we don’t enter the correct extension of the file that we want to open. People who writes companion viruses will be knowing what all filenames the users are likely to enter in the MS-DOS prompt. And they will write companion viruses with the filename as those which they think the users will be typing in the command prompt with no extensions.

Sector Viruses

One of the other rarest viruses is boot sector virus. These are viruses that are spread through floppy disks. For the same reason, now a day these viruses are not found. People have started using optical disks and have completely forgotten the outdated way of storing files (using floppy disks). From the name, you might have thought that, it would be a virus that affects the boot sector. But that’s not its job. Its job is to harm the whole hard disk itself and not just the files or the boot sector. Boot sector viruses reside in the boot sector of hard disks. This is why some antivirus programs recommend scanning the boot sectors of hard disk before they start scanning the system for the first time.